1. Field of the Invention
The present invention relates to the secure authentication of computer-interfaceable hardware tokens such as smartcards and USB tokens.
2. Description of the Related Art
In the last decade, the use of personal computers in both the home and in the office have become widespread. These computers provide a high level of functionality to many people at a moderate price, substantially surpassing the performance of the large mainframe computers of only a few decades ago. The trend is further evidenced by the increasing popularity of laptop and notebook computers, which provide high-performance computing power on a mobile basis.
The widespread availability of personal computers has had a profound impact on interpersonal communications as well. Only a decade ago, telephones or fax machines offered virtually the only media for rapid business communications. Today, a growing number of businesses and individuals communicate via electronic mail (e-mail). Personal computers have also been instrumental in the emergence of the Internet and its growing use as a medium of commerce.
While certainly beneficial, the growing use of computers in personal communications, commerce, and business has also given rise to a number of unique challenges.
While it reflects a tremendous advance over telephones and facsimile machines, e-mail also has its problems. One of these problems involves security. Telephone lines are relatively secure and a legally sanctioned way to engage in the private transmission of information, however, e-mails are generally sent over the Internet with no security whatsoever. Persons transmitting electronic messages must be assured that their messages are not opened or disclosed to unauthorized persons. Further, the addressee of the electronic message should be certain of the identity of the sender and that the message was not tampered with at some point during transmission.
Although the packet-switching nature of Internet communications helps to minimize the risk of intercepted communications, it would not be difficult for a determined interloper to obtain access to an unprotected e-mail message.
Many methods have been developed to secure the integrity of electronic messages during transmission. Simple encryption is the most common method of securing data. Both secret key encryption such as DES Data Encryption Standard) and public key encryption methods that use both a public and a private key are implemented. Public and private key encryption methods allow users to send Internet and e-mail messages without concern that the message will be read by unauthorized persons or that its contents will be tampered with. However, key cryptographic methods do not protect the receiver of the message, because they do not allow the recipient to authenticate the validity of the public key or to validate the identity of the sender of the electronic message.
The use of digital certificates presents one solution to this problem. A digital certificate is a signed document attesting to the identity and public key of the person signing the message. Digital certificates allow the recipient to validate the authenticity of a public key. However, the typical user may use e-mail to communicate with hundreds of persons, and may use anyone of several computers to do so. Hence, a means for managing a number of digital certificates across several computer platforms is needed.
Internet commerce raises other challenges. Users seeking to purchase goods or services using the Internet must be assured that their credit card numbers and the like are safe from compromise. At the same time, vendors must be assured that services and goods are delivered only to those who have paid for them. In many cases, these goals are accomplished with the use of passwords. However, as Internet commerce becomes more commonplace, customers are finding themselves in a position where they must either decide to use a small number of passwords for all transactions, or face the daunting task of remembering multiple passwords. Using a small number of passwords for all transactions inherently compromises security, since the disclosure of any of the passwords may lead to a disclosure of the others. Even the use of a large number of passwords can lead to compromised security. Because customers commonly forget their password, many Internet vendors provide an option whereby the user can be reminded of their password by providing other personal information such as their birthplace, mother's maiden name, and/or social security number. This feature, while often necessary to promote Internet commerce, severely compromises the password by relying on “secret” information that is in fact, publicly available.
Even in cases where the user is willing and able to keep track of a large number of passwords, the password security technique is often compromised by the fact that the user is inclined to select a password that is relatively easy to remember. It is indeed rare that a user selects a truly random password. What is needed is a means for generating and managing random passwords that can be stored and recalled for use on a wide variety of computer platforms.
Smartcards and other hardware tokens provide some of the above-mentioned functionality, but to prevent the unauthorized use of such tokens and the compromise of the information stored therein, there is a need to authenticate such tokens to assure that the possessor of the token is in fact the person entitled to use the token to access the computer.
Typically, hardware tokens require the user to enter a password such as a personal identification number (PIN) before using the card. A token may be designed or configured to be used without a PIN, but that poses a security threat as anybody in possession of a token (whether by finding a lost token or by theft) could use the token without restriction, potentially compromising the data stored therein and possibly using the token to access other computer systems. What is needed is a system and method for securely authenticating hardware tokens. The present invention satisfies that need.